The answer to the question is- Fe2O3
The answer is 3.
<span>The relation between number of half-lives (n) and decimal amount remaining (x) can be expressed as:
</span>

We need to calculate n, but we need x to do that. To calculate what p<span>ercentage of a radioactive species would be found as daughter material, we must calculate what amount remained:
1.28 -</span> 1.12 = 0.16
If 1.28 is 100%, how much percent is 0.16:
1.28 : 100% = 0.16 : x
x = 12.5%
Presented as decimal amount:
x = 0.125
Now, let's implement this in the equation:
<span>

</span>
Because of the exponent, we will log both sides of the equation:


<span>

</span>


Therefore, 3 half-lives have passed <span> since the sample originally formed.</span>
Answer:
pH = 1.5
Explanation:
The pH is always equal to -log[H+].
Simply plug it into this formula to find the pH. In order to find the concentration from the pH, you can do:
= [H+]
Answer:
B. Polar Easterlies
C. Sub polar low
D. Prevailing westerlies
E. Sub tropical high
F. Tropical easterlies
G. Inter tropical convergence zone
H. Tropical easterlies
I. Sub tropical high
J. Prevailing westerlies
K. Sub polar low
L. Polar easterlies
Explanation:
H₃PO₄ is stronger acid than H₃AsO₄.
H₃PO₄ is the stronger acid because PO₄is more electronegative than Se so PO₄3- is more stable than AsO₄3-.
<h3>Acid definition</h3>
Any substance that tastes sour in water solution, turns blue litmus paper red, reacts with some metals to release hydrogen, reacts with bases to form salts, and stimulates chemical reactions is considered an acid (acid catalysis).
An acid is a chemical substance, typically a liquid, that contains hydrogen and can interact with other substances to form salts. Some acids react with other materials and burn or dissolve them.
Acids are frequently encountered in daily life. They exist naturally in foods, are found in cells and digestive systems, and are used in numerous regular chemical reactions. Strong acids that are frequently used include nitric acid, phosphoric acid, sulfuric acid, and hydrochloric acid.
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